Adherent cells avoid polarization gradients on periodically poled LiTaO3 ferroelectrics.

The response of fibroblast cells to periodically poled LiTaO3 ferroelectric crystals has been studied. While fibroblast cells do not show morphological differences on the two polarization directions, they show a tendency to avoid the field gradients that occur between polarization domains of the ferroelectric. The response to the field gradients is fully established after one hour, a time at which fibroblasts form their first focal contacts.

Differences between healthy hematopoietic progenitors and leukemia cells with respect to CD44 mediated rolling versus adherence behavior on hyaluronic acid coated surfaces.

We previously demonstrated that leukemia cell lines expressing CD44 and hematopoietic progenitor cells (HPC) from umbilical cord blood (CB) showed rolling on hyaluronic acid (HA)-coated surfaces under physiological shear stress. In the present study, we quantitatively assessed the interaction of HPC derived from CB, mobilized peripheral blood (mPB) and bone marrow (BM) from healthy donors, as well as primary leukemia blasts from PB and BM of patients with acute myeloid leukemia (AML) with HA. We have demonstrated that HPC derived from healthy donors showed relative homogeneous rolling and adhesion to HA.

The biocompatibility of metal-organic framework coatings: an investigation on the stability of SURMOFs with regard to water and selected cell culture media.

Highly porous thin films based on a [Cu(bdc)(2)](n) (bdc = benzene-1,4-dicarboxylic acid) metal-organic framework, MOF, grown using liquid-phase epitaxy (LPE) show remarkable stability in pure water as well as in artificial seawater. This opens the possibility to use these highly porous coatings for environmental and life science applications. Here we characterize in detail the stability of these SURMOF 2 thin films under aqueous and cell culture conditions.

Fibroblast adhesion on unidirectional polymeric nanofilms.

Nanotextured polymeric surfaces with inclined rods reveal highly anisotropic properties concerning wetting and adhesion. In this work, we report on the interaction of fibroblast cells with these highly anisotropic materials. The authors quantified removal of adherent cells from such surfaces by a laminar flow.

Shear stress regulates adhesion and rolling of CD44+ leukemic and hematopoietic progenitor cells on hyaluronan.

Leukemic cells and human hematopoietic progenitor cells expressing CD44 receptors have the ability to attach and roll on hyaluronan. We investigated quantitatively the adhesion behavior of leukemic cell lines and hematopoietic progenitor cells on thin films of the polysaccharides hyaluronan and alginate in a microfluidic system. An applied flow enhances the interaction between CD44-positive cells and hyaluronan if a threshold shear stress of 0.

Quantification of the adhesion strength of fibroblast cells on ethylene glycol terminated self-assembled monolayers by a microfluidic shear force assay.

The adhesion strength of cells depends on the properties of the surface they attach to. Varying the surface properties can trigger different cellular responses such as differentiation. In order to study cell adhesion quantitatively, we developed a microfluidic shear force assay which allows the variation of applied shear stress by five orders of magnitude.

Digital in-line holography with femtosecond VUV radiation provided by the free-electron laser FLASH.

Femtosecond vacuum ultraviolet (VUV) radiation provided by the free-electron laser FLASH was used for digital in-line holographic microscopy and applied to image particles, diatoms and critical point dried fibroblast cells. To realize the classical in-line Gabor geometry, a 1 microm pinhole was used as spatial filter to generate a divergent light cone with excellent pointing stability. At a fundamental wavelength of 8 nm test objects such as particles and diatoms were imaged at a spatial resolution of 620 nm.